Here you have them in alphabetical order as reported by The Denver Post. Not all resorts included but thats a fair chunk. The epic amount of snow this season has extended spring skiing for many resort but all dates are subject to change:
Arapahoe Basin:Â June 2
Aspen Highlands:Â daily through April 14, plus April 19-21 and April 26-28
Aspen Mountain:Â April 21
Beaver Creek:Â April 14
Breckenridge:Â May 27
Buttermilk:Â April 7
Ski Cooper:Â April 7
Copper Mountain:Â April 21
Crested Butte:Â April 7
Echo Mountain:Â April 14
Eldora:Â April 21
Granby Ranch:Â March 31
Hesperus:Â daily through March 17, Friday through Sunday thereafter through March 31
Howelsen Hill:Â closed
Kendall Mountain:Â March 31
Keystone:Â April 7
Loveland:Â May 5
Monarch:Â daily through April 7, Friday-Sunday through April 21
Powderhorn:Â March 31
Purgatory:Â daily through April 7, Saturdays and Sundays thereafter with closing date TBD
Silverton:Â April 14
Snowmass:Â April 21
Steamboat:Â April 14
Sunlight:Â April 7
Telluride:Â April 7
Vail:Â April 21
Winter Park:Â April 21 (Mary Jane May 12)
Wolf Creek:Â daily through April 7, Friday-Sunday thereafter through April 21
images from Arapahoe Basin Facebook Page